Presently known compressors used in refrigeration and air conditioning systems such as variable displacement swash plate compressors, for example, typically include a lubricating mist suspended in a gaseous refrigerant medium. Such compressors also include a first path that provides refrigerant communication between a crank chamber and a discharge chamber, and a second path that provides refrigerant communication between the crank chamber and a suction chamber. During operation of the compressor, the oil mist lubricates moving parts of the compressor. However, oil that remains suspended in the refrigerant as it travels throughout the refrigeration and air conditioning system can minimize a performance and an efficiency the refrigeration and air conditioning system.
To combat these problems, an oil separator is added to the refrigeration and air conditioning system. One type of oil separator is typically positioned in the refrigeration and air conditioning system between the compressor and a condenser. The oil separator functions to separate the suspended oil from the gaseous refrigerant, so that the oil is maintained in the compressor and introduced into the suction chamber. This type of oil separator requires added package space in the discharge chamber or a separate external component attached to the compressor.
A second type of oil separator utilizes the crank chamber to store the oil, so that the oil is maintained in the compressor and not introduced into the suction chamber. However, the addition of this type of oil management system in the refrigeration and air conditioning system does not address other operating conditions of the compressor which may lead to performance and durability issues such as liquid-fill start-up, high-temperature operation, or inadequate piston lubrication at high speeds caused by oil logging in the crank chamber of the compressor, for example.
It would be desirable to produce a variable displacement compressor wherein a performance, an efficiency, and a durability of the compressor are maximized, and a cost of manufacture, a weight, a package size, and an assembly time thereof are minimized.